Process of treating ores.



'cially' from those ores which cannot [UNITED STATES PATENT OFFICE.

FREDERICK MILTON JOHNSON, OF SAN FRANCISCQ, CALIFORNIA.

rnocnss F TREATING omss.

sidingat San Franciscoi, in the county of San Francisco and State o California, have inv ,yented certain new and useful Im rov nents 1n Processes of Treating Ores, o whichthe following is a specification. I Y

My invention relates to the extraction of the precious materials from ores, and espebe effect- 1 ivelytreated by concentration, amalgamation or like processes. Such are sulfid, and

" of the soda solutions w i k nd yield readily ing] settling. While Some ores of this to the treatment by the cyanid process, ut require to be prec-i itated by zinc shavings in order to recover t e values; andpne object of my invention is to do awaywi'th the use of such zinc shavings,

'ticand arsenical ores.

and substitute thcrefor'simple precipitating plates, v v V My process comprises broadly the mixing with the solution in the c' aniding tank of any liich dissolve silver,

su erior action is obtained.

11 treating sulfids and pyritic and arsenical ores the ore is put into. a tank containing a so ution of caustic soda, and which is rovided with some kind of agitating device or keeping the mass stirred up and'preventalgitated, it is subg'ected to the action of an e ctric current 0 high ampera e and low voltage derived from any suitable source of electrical energy. The result of the com bined chemical and electrical actions, on ores I of this character, is to remove sulfur and arsome, .to remove-any 11011 resent, to wholly 10 or partially dissolve any ver, and to effect a general decomposition of the mass which i 'puts it in better condition for the cyaniding.

After this treatment, the whole mass, wlthout anyfurther separation,goes directly into .145

. previously alludedto, that t e solution of the cyanid tank, and this e )lains what -I caustic soda is indirectly mixed with the cyanid solution when thispreliminary'treatment is employed. vIn the cyanid tank the Specification of Letters Patent. Application filed June 3. i934. Serial No. 211.051-

the silver being dissolved.

in this tank and being soda solution in the cyanid tank, the cyanid Patented Dec. '17, 1907.

gold is dissolved by the c anid, and the caustic soda continues its sovent action on the silver, both working in harmony upon the said metals.

When the c *anid treatment has been completed, and the mass is ready for precipitation, I use, instead of the customary zinc shavings, simple plates of zinc and aluminium which are preferably bound together with copper strips. I prefer to usea fiat plate of zinc between two flat plates of aluminium, riveting co per strips around the ends so as to bind all together into a single structure. I have found that with a plate of this character a perfect precipitation of both gold and silver is efiected.

If the ore requires no preliminary treat ment, and is placed directly in the cyanid tank, the proportion vof caustic soda to c anid should be about equal in volume. f the preliminary treatment is-required, the

amount of the'solution of caustic soda used in'the decomposing tank, should be such that when the mass is transferred to the cyanid tank, the proportion of caustic soda shall 'be about equal in volume to theamount of cyanid. a i

Heretofore, the recovery of silver by the ordinary c anid process, as been ve imperfect an unsatisfactory; onl aportionof 11 using the solution acts as heretofore on. the gold, and the'soda solution acts directl upon the silver,'in perfect harmony wit the cyanid, thereby completely dissolving both metals. In addition the two solvent elements thus combined, form a chemical solution that acts upon my plates, giving a perfect precipitation and doing away entirely with zinc shavin s.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

The hereindescribed method of treating sulfids and pyritic arsenical ores, which consists in placing the ores in a tank containing a solution of'caustic soda, agitating the contents ofthe tank, during such agitation subjecting the contents to the action of an elec- In testimony whereof I have affixed my tric current of high amperage and low volsignature, inpresence of two Witnesses, this tage, then transferring the entire mass or contWenty sixth day of April 1904;

tents of the tank to a cyanid tank and sub FREDERICK MILTON JOHNSON. 5 jecting it to the action of a, solution of cy- W1tnesses:

anid of potassium in the presence of caustic L. W. SEELY,

soda, su bstantially as described.' M. R. SEELY. 

